3 give up comfort apartmentA ´ = {x | x is a member of U, but not as A member of x}.4 the differenceA-B = {x | x is a member of A, but not a member of B}.
3 comments SUPPLEMENTS A'= {x | x is a member of the U, but x is not a member of A} 4 different AB = {x | x is a member of A, but not a member of the B}.